Multiple axle drive



J y g, 1952 G. w. CARLSON MULTIPLE AXLE DRIVE 5 Sheets-Sheet l FiledJune 5, 1950 IN V EN TOR. GUSTAV. W. CARLSON W ATTO R N EYS G. w.CARLSON 2,603,108

July 15, 1952 MULTIPLE AXLE DRIVE Filed June 5, 1950 3 Sheets-Sheet 2 EF-| E 2 o I II o t' 1 \,9, In 1 0 I q. I 0 8 r0 8 a a y N k "a Q 8INVENTOR. g g GU STAV w-cARLsoN G. w. CARLSON 2,603,108

July 15, 1952 MULTIPLE AXLE DRIVE '5 Sheets-Sheet 5 Filed June 5, 1950Ji l-E Li,

INVENTOR.

GUSTAV W. CARBON ATTO R N EYS Patented July 15, 1952 Mpnrirrn AXLE DRIVEGustav W. Carlson, Cleveland Heights, Ohio, assignor to EatonManufacturing Company, tlleveland, Ohio, a corporation of OhioApplication June 5, 1950, Serial No. 166,261

ferential gear set that will permit of the transportation of heavierloads especially wherein the driving torque of the low gear range of thetwo gear ratio axle can be utilized as required, that is electricalshift controlled to provide for the same or different gear ratiooperation of the axles simultaneously, that is provided with means forlocking .up the differential gearing between the axles when they are tobe operated at the same gear ratio, and that is provided with means forpreventing the lock up operation of the differential gearing between theaxles when the axles are operating at different gear ratios' Otherobjects and advantages of the invention will appear from the followingdescription taken in connection with the drawings forming a part of thespecification and in which:

Fig. 1 is a top plan view of the rear of a vehicle employing atandernaxle drive embodying the present invention;

Fig. 2 is a fragmentary mostly cross-sectionalized view of thedifferential gearing of the separate axle drives and the interconnectingdiiferential gearing therefore; V

Fig. 3. is a schematic illustration of theelec= trical control systemforthe tandem axle drive shown by Fig. 2; and V Fig. 4 is a schematicillustration of thetwo field reversible motor and circuit therefore'utilized in the apparatus of Fig. 3.

Similar reference characters indicate corresponding parts throughout theseveral views of the drawings. v

The present invention is predicated upon the provision of a tandem axledrive which is adaptable to the transportation by vehicles of heavierloads than might be otherwise possible where it is requisite undercertain conditions of vehicle operation that-additional driving torquebe available to allow the vehicle to negotiate hilly terrain or thelike. This requirement is obtainable through the provision of separatedrive axles interconnected by a differential gear set-and where- 7'Claims. (o1. 74-410) r "z inone axle is operable at one gearv ratio andthe other axle is operable at two gear ratios, said'two gear ratio axlebeing electrical shift controlled for the desiredratio operation thereofas drive conditions require. Provision is made for locking up thedifferential gear-set interconnected between theaxles to permit ofdirect drive through from the source of power to the'respective axleswhen the axles are operating at the same gear ratio. As a means ofinsuring that the differential gear set will not be locked up when theseparate axles are operating atdifferent gear ratios electricallyactuated detent means are controlled from an electrical shift controlapparatusfor the two gear ratio axle, eife'c tive to insure functionaloperation of th differential gear set when the two gear ratio axle isoperating in low. Furthermore, when the differential gear set is lockedup the electrical shift control apparatus is inoperative to effect ashift of the twogear ratio axle to'a speed ratio different from theotheraxle. With the differential gear set not locked up, it is possibleif desired upon the shifting of the twospeed axle to the same gear ratioas the other'axle, by the electrical apparatus therefore, to lock up thedifferential gear set'by virtue of simultaneous electrical release ofthe diiferentialgea'r set lockup means and the manual shifting thereofto lock out position. Y

Referring to the drawings for more specific details of the invention It)represents generally, as shown by Fig. 1, the fragmentary illustrationof a vehicle to which the present invention is applied, including aframe it extending across and supported on a pair of axle housings I4and it. The axle housings I land it have connected therethrough at theends thereof dual wheels I8 and 29 respectively. The forward axlehousing it carries a double casing 22, the purposeof which willhereinafter appear, the front end of which supports a power drivingconnection 24, adaptedto be connectedin a conventional manher with apower driven speed change transmission, not shown. r

The connection 24 forms one end of a drive shaft 26 to which is splineda spider 28 having beveled idler gears 33, of a differential gear set32., supported for rotation thereon. Th idler gears 38 havemeshingengagement in one axial direction along shaft 26 with a beveledgear 34 of a gear member 36 and on their other side, axially disposedalong the shaft from beveledgear 3t, with abeveled gear 38 of a gearmember 40.; g The gear members 36 and 40 are providedrespectively withlike gears 42 and 44, gear 42 meshing with a power input gear 46connected through shaft 48 and beveled gear 50 with a differentialsingle gear ratio set 52 for the forward axle drive 54 mounted in axlehousing I4 whereas gear 44 meshes with a gear 55 splined to acountershaft, 56. The countershaft 56 is connected by suitable connector58 with an extension shaft 60 which, in turn, is connected by suitableconnector 62 to a power input shaft 64. Power input shaft 64 supports insplined relation on its freeend a beveled gear 66 which hasmeshingjengagement with a beveled gear 68 of a two ratio differentialgear set I for the rear axle drive I2 mounted in axle housing I8.

Whereas the differential gear set 52 and axle drive 54 are of theconventional. typesuchasds generally disclosed by G. Carlson et al..Pat.No. 2,417,145, the two ratio differential gear set I0 and rearaxle driveI2 are of the conventional type disclosed by R. G. Russell Pat. No.2,462,719. The two ratio gear set 14- of the axle drive 12 includes a,planetary gearing system I6, the sun gear I3 of which is axiallyshiftable between two positions, one in which the normal speed ratiofunction of the planetary gear-system is operative and the other whenthe planetary gear system is-locked up for straight drive therethroughat the'same speed ratio as the axle drive 54 thereby providing: for thelike ratio of operation of both axle drives to the input gear of therespective differential gear sets 52 and 10.

Sun gear III forms part: of a quill shaft 80which is axially movable"therewith under the influence or: an electrical. motor actuated yoke. 82having engagement at: one axial end of: the. quill oppositeiy' axiallydisposed fromthe sun gear- I8 end thereof.

The operationxof. the axle speed shifting" yoke 82' is eii'ected. by' areversible electric motor 04 forming part of an electrical shiftmechanism 86' having a manually controllable electrical circuit 30.Theelectrical shift mechanism and circuit 00 are generally disclosed byaforementioned Pat. No. 2,462,779 utilized in a like manner as disclosedherein for electrically controlling the shift operation of the ratioaxle drive, such as forms a; part of this invention.

Itisto be-noted in viewing-theeschematiczelectrical shift control ofFig. 3 that the operation of the reversible electric motor is controlledthrough circuit 86: by a manually operable two placeswitch30 such thatupon the-normalclosing of thecircuit across contact points. 32 and 94anoperation of the motor is effected as supplied electricalcurrentthrough. the circuit from an electrical. storage. battery 36; byway of. branch electrical line.9.0 of circuit 83.. A. normalumovement.of switch 90 to close" the circuit across con; tact. points I00 and I02effects a flow ofv current from. thebattery by way of branch electricalline I 04 for the reversal of operation of the motor fromthat. effectedthrough branch line. 38. Theclosing of the switchacross contacts 92 and94 corresponds to a shift of the; axle drive to high. that is a.movement of the. yoke to the right as, viewed in Fig. 2. to. cause alock-up engagement of therplanetary gearing system. I6 through themovement. of. the. sun gear 10. into locking mesh. with the planetpinions I06 thereof.

The electrical. control circuit 68 for the. shift control operation ofthe axle drive. I2 has assoelated therewith a. solenoid. I 08. connectedinparallel by way of. branchelectrical line I I0. tiedinto branch. line36, the armaturev .2 of which. is

4 resiliently loaded in one direction by a spring I I4 and carries atits free extremity a detent I I0.

The detent II6 forms one part of a locking device utilized inconjunction with an axially shiftable member I I3 for controllablyrestraining the movement thereof under certain conditions by theengagement thereof with a slot I20 formed in the peripheral surfacethereof.

The shiftable member H8 is in the form of a yoke having one end I22thereof connected to a shift operating arm I23 such that when it is notrestrained from movement by detent II6 it is effective upon the axialmovement thereof through the engagement arrangement of the yoke with aclutch member I24, splined for axial movement on shaft 26, to move theclutch member I24 axially on the shaft. The clutch member I24 isprovided at one end internally thereof with clutch teeth I26 adapted tohave meshing engagement with clutch teeth I28 formed on gear member 36for, inhibiting, upon. engagement therebetween, rotation of the gearmember; 36 relative to. shaft 26.. With thev locking of. gear member 36to shaft. 26 the differential. gear set becomes a unitary operating partof the. shift and operates entirely in unison therewith, thereby duringthisphase of operation losing its function as a differential mechanism.

Shiftable member H8 in addition to its association with solenoidactuated detent H8 is engageable in its locked axial position on shaft26 with a pivotal spring tensioned member I30 forming part of anelectrical switch I32 arranged in thebranch line I34 of. the electricalcircuit 00 intermediate the electrical current source and themanualswitch 92. Contact points I30 and I38 of switch I32 are normallyin electrical contact so long as the shiftable member H3 is in aposition wherein the. clutch member I24 is out of engagement with thegear member 36, but will bespaced apart out of contact by pivotalmovement of switch member I30 when the shiftable member H8 is movedunder the influence of shifting arm I23 to lock. the clutch member I24to gear. member 36.

With the arrangement ofthe solenoid I00 connected in the branch.electrical line 98; it is obvious that upon the manual shifting of theswitch to the position corresponding to high ratio axle gearing for axledrive I2 the solenoid will be energized simultaneously with theoperation of mOtOr 34, effective to release the detent from en.-gagement with shiftable member H8 and. thus permit the shifting ofclutch member I24 into locking engagement with gear member 36 for thelock-up operation of'the differential gear set 32.

Once the clutch member I 24 is clutched to gear member 36, which is,permissible solely when the rear drive axle I2 is operating at the samespeed ratio, as the front drive axle 54, no. shift of. the rear axledrive to low is possible inasmuch as a manual shift of switch 30 to lowacross contacts I00 and I02 is ineffective to supply current to themotor for its reverse operation because at this time the electricalcircuit is open throughswitch I32 and cannot function to supply currenttherethrough until the differential gear set 32 is releasedfrom lockedup condition.

Thus with the operational control between. the shifting of the rear axledrive I2 and thedifierential gear set 32 the differential gear set 32willbe operable to divide the driving power between, the

front and rear axle drives in accordance withthe speed ratiosofoperation but may be locked out. of power dividing operationifsodesired. only when the axle drives are operating in the same gear ratio.

While this invention has been described in connection with certainspecific embodiments, the principle involved is susceptible of numerousother applications that will readily occur to persons skilled in theart. The invention is, therefore, limited only as indicated by the scopeof the appended claims.

What I claim is:

1. A multiple axle drive comprising the combination of a power inputshaft, a differential gear set drivingly connected therewith, a singlespeed geared axle drivingly connected to the differential gear set, amultiple speed ratio geared axle drivingly connected to the differentialgear set, means for locking up the differential gear set for straightdrive therethrough, means for shifting the gearing of the multiple speedaxle, and means responsive to the axle gearing shifting means forcontrolling the differential'locking up means.

2. A claim according to claim 1 wherein the multiple speed ratio gearedaxle is a two speed ratio gearing arrangement.

3. A claim according to claim 1 wherein the axle gearing shifting meansis electrically con trolled.

4. A claim according to claim 3 wherein the means for controlling thedifferential locking up means includes an electrically operated solenoidconnected in an electrical circuit having a part afiixed to the armatureof the solenoid engageable with the differential gear set locking upmeans for restraining movement thereof to lock up the diiferential gearset when the electrical circuit to the solenoid is inoperative.

5. A multiple axle drive comprising the combination of a power inputshaft, a differential gear set drivingly connected to said power inputshaft, a differential single speed ratio geared axle structure drivinglyconnected to the differential gear set, a differential two-speed ratiogeared axle structure drivingly connected to the differential gear set,a manually controlled electrically operated shift means for the gearingof the two-speed ratio axle, a shiftable lock up device for thedifferential gear set, means engageable with said shiftable lock updevice for controlling the movement thereof, and means incorporatedbetween the electrically operated shift means for the gearing of thetwo-speed ratio axle and the differential gear set movement controllingmeans for establishing a fixed relationship of operation therebetween.

6. A multiple axle drive comprising the combination of a power inputshaft, a differential gear set drivingly connected to said power inputshaft, a differential single speed geared axle structure drivinglyconnected to the differential gear set, a differential two-speed ratiogeared axle structure drivingly connected to the differential gear set,an electrically operated mechanism for shifting the gears of the twospeed ratio axle, an electric circuit having a pair of parallel branchesfor supplying current to the electrically operated shift mechanism froma source of power, a shiftable lock up device for the differential gearset, a two place manual switch in the electric circuit operablealternately with the branches thereof for supplying current to theelectrically operated mechanism, a spring tensioned normally open switchin the electric circuit intermediate the source of power and manualswitch, and an electrically operated solenoid connected in one branch ofthe electric circuit for one controlled axle shift position having apart affixed to the armature of the solenoid thereof engageable with thelock up device to restrain the movement thereof when the solenoid isdeenergized and to release the lock-up device for permissible movementwhen the solenoid is deenergized, said lock up device when in disengagedposition maintaining the spring tensioned switch closed.

7. A multiple axle drive comprising a power input shaft, a differentialsingle speed geared axle structure, a differential two-speed ratiogeared axle structure, the high ratio gear of which is identical withthe gear ratio of the single speed axle, a differential gear setdrivingly connected intermediate the input shaft of the axle structureand the gearing of the single speed axle and the two speed axlestructures, a reversible electric motor operated gear shifting mechanismfor the two-speed ratio axle, an electrical current supply system forthe two-speed ratio axle, an electrical current supply system for themotor of the gear shifting mechanism including a source of electricalpower, a pair of parallel branch circuits one corresponding to the highgear shift position of the axle and the other to the low gear shiftposition of the axle, and a manually actuated switch to alternatelyconnect the source of power to one or the other of the branch circuits,a shiftable device for locking up the differential gear set for straightthrough power delivery from the power input shaft to the axlestructures, an electrically operated solenoid connected in series in thehigh gear branch circuit of the electrical system having an armaturethereof engageable with the differential gear set locking up device torestrain the movement thereof when the manual switch connects the lowgear branch circuit to the source of power, and a spring tensionedelectrical switch in circuit intermediate the source of power and manualswitch engageable by the looking up device when inoperative to lock outthe differential gear set to maintain the switch closed and tensioned toopen position when the differ- 1ential lock up device is shifted tooperative posiion.

GUSTAV W. CARLSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Welles June 27,1944

